Both robes are signed by Frazier and will go on sale as part of the "Heavyweights & Headliners: Legends in Sports and Rock" auction presented by Bonhams.

Bids begin at $50,000 (first fight) and $75,000 (third fight) and are estimated to sell between $100,000 to $150,000 each. The online auction ends on February 25.

The items are drawn from the collection of longtime Madison Square Garden photographer George Kalinsky, who died last year at 88. The auction also features Ali-Frazier-related photographs taken by Kalinsky as well as memorabilia from other sports.

Frazier won the first fight against Ali by unanimous decision in 1971 at New York's Madison Square Garden; the bout was billed as “The Fight of the Century.”

Frazier lost the rematch by unanimous decision at the same venue in 1974.

The third fight was billed as the "Thrilla in Manila" in 1975 and Frazier ended up suffering a 14th-round stoppage in the Philippines.

In recent years, collectors have opened their checkbooks to secure relics from the Ali-Frazier rivalry.

Ali’s trunks from the third fight sold for $1.2 million last year and the gloves Ali wore in the first fight sold for $606,375 in 2016. The red robe Ali wore in the third fight sold for $348,000 in 2022. The WBC belt that Ali won from George Foreman during the “Rumble in the Jungle” in 1974, and defended against Frazier in the third fight, sold for $6.1 million in 2022.